shape-margin CSS property

shape-margin: 0;

shape-margin: 20px;

shape-margin: 1em;

shape-margin: 5%;

<section class="default-example" id="default-example">
 <div class="example-container">
 <div class="transition-all" id="example-element"></div>
 We had agreed, my companion and I, that I should call for him at his house,
 after dinner, not later than eleven o'clock. This athletic young Frenchman
 belongs to a small set of Parisian sportsmen, who have taken up "ballooning"
 as a pastime. After having exhausted all the sensations that are to be found
 in ordinary sports, even those of "automobiling" at a breakneck speed, the
 members of the "Aéro Club" now seek in the air, where they indulge in all
 kinds of daring feats, the nerve-racking excitement that they have ceased to
 find on earth.
 </div>
</section>

.example-container {
 text-align: left;
 padding: 20px;
}
#example-element {
 float: left;
 margin: 20px;
 width: 180px;
 height: 180px;
 border-radius: 50%;
 background-color: rebeccapurple;
 shape-outside: circle(50%);
}

/* <length> values */
shape-margin: 10px;
shape-margin: 20mm;
/* <percentage> value */
shape-margin: 60%;
/* Global values */
shape-margin: inherit;
shape-margin: initial;
shape-margin: revert;
shape-margin: revert-layer;
shape-margin: unset;

<section>
 <div class="shape"></div>
 We are not quite sure of any one thing in biology; our knowledge of geology is
 relatively very slight, and the economic laws of society are uncertain to
 every one except some individual who attempts to set them forth; but before
 the world was fashioned the square on the hypotenuse was equal to the sum of
 the squares on the other two sides of a right triangle, and it will be so
 after this world is dead; and the inhabitant of Mars, if one exists, probably
 knows its truth as we know it.
</section>

section {
 max-width: 400px;
}
.shape {
 float: left;
 width: 150px;
 height: 150px;
 background-color: maroon;
 clip-path: polygon(0 0, 150px 150px, 0 150px);
 shape-outside: polygon(0 0, 150px 150px, 0 150px);
 shape-margin: 20px;
}

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